Spatiotemporal distribution of norovirus infection outbreaks in Chengdu

Objective  To analyze the spatiotemporal distribution of norovirus infection outbreaks in Chengdu with the geographic information system (GIS) and provide evidence for the prevention and control of norovirus infection. Methods  A database of the outbreaks of norovirus infection in Chengdu from 2014 to 2019 was established. The concentration ratio and circular distribution method were used to analyze the temporal clustering of the epidemic, and the Moran’s Ⅰ method was used to analyze spatial autocorrelation. Results  The M value of norovirus outbreaks in Chengdu was 0.3927872, which showed the temporal clustering of norovirus infection with higher incidence in winter and the incidence peak during November - March. The incidence was higher in central urban area than in suburban area, with different “hot spot” or “cold spot” in different seasons. Conclusion  There was obvious spatiotemporal clustering of norovirus infection outbreaks in Chengdu, suggesting that the prevention and control of norovirus infection should be strengthened in key area and period.